India's latest fourth generation satellite INSAT-4B aimed to give a fillip to Direct-to-Home TV transmission began its space odyssey on Monday as it successfully hurtled into a geosynchronous transfer orbit by a heavy Ariane-5 launcher at the spaceport of Kourou in French Guyana.

The Ariane-5 blasted off at around 4.33 am with twin passengers of the British Military satellite Skynet 5A and INSAT-4B. In a precise operation, the launch separated INSAT-4B for around 31 minutes after the launch.

The Indian Space Research Organisation, in a release in Bangalore, said the satellite launched in 3-axis stabilised mode "is now orbiting the earth once in 10 hours and 34 minutes." Its perigee (nearest point to earth) was 243 km with an apogee (farthest point to earth) of 35,876 km and an inclination of 4.52 degree with respect to the equator.

The 3025 kg satellite would be, over the next few days, manoeuvred to its space home of 93.5� east longitude where it would be co-located with INSAT-3A.

With 12 high-powered Ku-band transponders and 12 C-band transponders, INSAT-4B will further augment the INSAT capacity for the DTH television services and other communication and TV services.

Once INSAT-4B is commissioned, India would have a total transponder capacity of 199 in the INSAT constellation of communication satellites.

The over Rs 200 crore satellite would also be a commercial success as each of the 24 transponders is expected to bring in a revenue of little over $1million dollars per year during its 12-year mission life.

ISRO Chairman G Madhavan Nair termed the launch an important one to the country and complimented Arianespace for a precise launch.

The satellite is the 13th to be launched from Kourou.

Space controllers at the Master Control Facility at Hassan in Karnataka acquired the first signals from INSAT-4B at 4.02 am.

The initial checks on the satellite have indicated its normal health.

The MCF subsequently issued commands to the satellite to make the earth viewing face to orient towards earth. The calibration of the gyros on board the satellite was also carried out.

The satellite's orbit is being precisely determined by continuous ranging from the participating ground stations across the globe.

In the coming days, INSAT-4B will be maneuvered to its final geostationary orbit, which is about 36,000 km above the equator, by firing its 440 Newton Liquid Apogee Motor. When the satellite reaches near geosynchronous orbit, deployment of its solar panels and the two antennas would be carried out and the satellite put in its final 3-axis stabilised mode.

This would be followed by trim maneuvers to take the satellite to its designated orbital slot. The payloads would be checked before the commissioning of the satellite.

Meanwhile, Parliament on Monday congratulated ISRO scientists for the successful launch of INSAT-4B. "We are proud of them," Lok Sabha Speaker Somnath Chatterjee said while complimenting "great scientists and their wonderful service to the nation."

In a statement, Minister of State in the Prime Minister's Office Prithviraj Chavan informed members that India's newest satellite INSAT-4B was successfully launched early on Monday morning by the European Ariane-5 launch vehicle from Kourou, French Guyana.